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rwells36 · 31-10-2016, 12:50

If I wired my inverter batteries for 24v instead of 12v and installed an isolator / acr in front of my 24v alternators X 2 engines; then this would give me 140 amps (once the pair of 24v cranking banks are topped off).

This would require an inverter of 24v > 110ac whereas as now the heart 2500 watt inverter has a 12v input. My 12v house banks would remain 12v for vessel instruments and navigation.

Scott Berg · 31-10-2016, 13:25

Bear with me on this one, I do a LOT of work on 24 and 32 volt boats.

Newmar (and others) make what you need. You DO NOT NEED a 12v battery bank; you just need to run your 12v loads. You can do this with a DC-DC converter. The one listed can be used for loads up to 30amps (peak to 35). We find that one or two can handle every 12v load on a 24 or 32 volt boat without having to maintain multiple battery systems.

Standard Series - DC Power Onboard

rwells36 · 31-10-2016, 13:45

If the engine were off would this product (below) allow the batteries to drain one another?

https://www.victronenergy.com/upload...olators-EN.pdf

Cadence · 31-10-2016, 13:47

Quote:

Originally Posted by Scott Berg

Bear with me on this one, I do a LOT of work on 24 and 32 volt boats.

Newmar (and others) make what you need. You DO NOT NEED a 12v battery bank; you just need to run your 12v loads. You can do this with a DC-DC converter. The one listed can be used for loads up to 30amps (peak to 35). We find that one or two can handle every 12v load on a 24 or 32 volt boat without having to maintain multiple battery systems.

Standard Series - DC Power Onboard

Appears to be light duty for electrics powering? One of the few people I've seen mention 32V, four 8V batteries. Most people would say you are crazy with the 32Volts. A real bastard.

Scott Berg · 31-10-2016, 13:59

Quote:

Originally Posted by Cadence

Appears to be light duty for electrics powering? One of the few people I've seen mention 32V, four 8V batteries. Most people would say you are crazy with the 32Volts. A real bastard.

The Newmar units can handle 30amps continuous, enough for fridge, radar, plotters, etc.

32v was the standard for years (taken from Railroad standards). You'll find that most old Chris Craft, Hatteras, and similar motor yachts are 32v based. We see them every day still but with time they are being replaced by 24v systems. In either case the Newmar DC to DC converters let us keep all the legacy 32 (or 24) volt systems in tact and still add new 12v based systems.

Cadence · 31-10-2016, 14:11

Quote:

Originally Posted by Scott Berg

The Newmar units can handle 30amps continuous, enough for fridge, radar, plotters, etc.

32v was the standard for years (taken from Railroad standards). You'll find that most old Chris Craft, Hatteras, and similar motor yachts are 32v based. We see them every day still but with time they are being replaced by 24v systems. In either case the Newmar DC to DC converters let us keep all the legacy 32 (or 24) volt systems in tact and still add new 12v based systems.

I had a 32V Correct Craft. One of the 5 flush deck motor yachts they made.

Starting batteries were 12volt.

My electronics knowledge is somewhat old at 73 since I got my degree in 63.

I would be interested in how it is done without going to AC and having large efficiency loses? Hell, I'm a dinosaur.

**Pete7** · 31-10-2016, 14:32

Quote:

Originally Posted by smac999

definitely don't do this... it won't work and you'll mess up your engine batteries in the process.

also the diode is useless as you will still be draining the engine battery into the house battery while not running the engine with or without it.

you need something voltage based so it only charged the house bank while the engine bank is under a charging voltage.

Oh good I am glad someone mentioned this because its not a good way of doing things and cost me a couple of batteries before I learnt the hard way.

Why not make the whole boat 24v? fridge and chart plotters will love it, the only thing I ever had a problem with was the VHF which at the time were 12v only in the UK.

Pete

rwells36 · 31-10-2016, 15:57

Hum. New electronics, pumps, lights, plotters etc., etc...? Seriously?

Mikado · 31-10-2016, 16:13

Quote:

Originally Posted by rwells36

Hum. New electronics, pumps, lights, plotters etc., etc...? Seriously?

You asked the forum for help with your situation and have gotten several options and excellent advice. This will resolve your issues:

Change your starter and both battery banks to 24V. Newmar or equiv DC/DC converter for 12V requirements. Xantrex DC/AC inverter charger for 110V.

If you have 12V, 24V DC and 110 AC requirements in my opinion this is the very best way to go.

rwells36 · 31-10-2016, 17:59

Seems the best to me as well (starter is 24v already). I do have to rewire some I suspect

smac999 · 31-10-2016, 23:41

Quote:

Originally Posted by Scott Berg

Bear with me on this one, I do a LOT of work on 24 and 32 volt boats.

Newmar (and others) make what you need. You DO NOT NEED a 12v battery bank; you just need to run your 12v loads. You can do this with a DC-DC converter. The one listed can be used for loads up to 30amps (peak to 35). We find that one or two can handle every 12v load on a 24 or 32 volt boat without having to maintain multiple battery systems.

Standard Series - DC Power Onboard

so your are going to run his 300a 12v inverter though a 24-12 converter?...

these are great if most of the boat is 24 and you only need to run a few things off 12. not convert the whole boat.

smac999 · 31-10-2016, 23:44

Quote:

Originally Posted by rwells36

If the engine were off would this product (below) allow the batteries to drain one another?

https://www.victronenergy.com/upload...olators-EN.pdf

no that is what it is designed for. but all the batteries need to be the same voltage as the alternator connected to it. you could use to to power both start batteries and your thruster battery from a single 24v alt. ( you still haven't said how the thurster battery gets charged from the 24v alt)

smac999 · 31-10-2016, 23:47

Quote:

Originally Posted by rwells36

If I wired my inverter batteries for 24v instead of 12v and installed an isolator / acr in front of my 24v alternators X 2 engines; then this would give me 140 amps (once the pair of 24v cranking banks are topped off).

This would require an inverter of 24v > 110ac whereas as now the heart 2500 watt inverter has a 12v input. My 12v house banks would remain 12v for vessel instruments and navigation.

this is another option if you want to buy a new inverter / charger. but you still need to charge the house battery from the engine. I have never seen a boat that didn't charge a house bank from engines.

you have many options. all with different amounts of work involved and cost.

rwells36 · 01-11-2016, 05:02

The boat was designed in Taiwan to operate the 17kw genset when away from the dock. That was the original intent and if operated that way I can run every thing on the vessel including 12v, 24v and inverter chargers all at once. I know owners who do precisely that and they arrive at their anchorage with batteries topped off. I just wanted to do the same without running the genset.